A system software component that is external to the operating system kernel. If the phrase is used to refer to the operating system itself, it is redundant because an operating system "is" software.

Real-time and embedded systems operate in constrained environments in which memory and processing power are limited. They must provide their services within strict time deadlines to their users and to ...

The computer's master control program. When a computer is turned on, a small "boot program" loads the operating system. Although additional system modules may be loaded as needed, the main part, known ...